1. Field of the Disclosure
The present disclosure relates generally to a camera apparatus, and more particularly, to an autofocusing apparatus and method for use with a camera.
2. Description of the Related Art
A camera using an autofocusing apparatus may include an autofocus (AF) lens that passes and/or refracts light to adjust focus of an image. Such a camera can automatically move an AF lens according to a predetermined focus, without requiring user operation.
In a conventional method for moving an AF lens in an optical axis direction, an actuator rotates a barrel including a cam and the AF lens moves along with the cam. In order to reduce the number of components, simplify structure, and improve autofocusing speed, recently cameras have been configured with a linear type drive unit by which an actuator moves lenses directly in the optical axis direction. For example, a motor, a piezoelectric element and a vibrator, or electromagnetic force have been used in a linear type drive unit.
Recently, a need has emerged to control the movement of a heavier AF lens at a high speed because lenses having a heavier material are being used and the number of lenses has increased in order to improve image quality. However, a conventional AF camera using a motor may not be suitable for moving these heavier lens because of limitations in output power. While additional gears have been used to overcome the weight limitation, which may improve the efficiency of torque transmission, it disadvantageously generates noise.